Abstract: A pump/motor includes a stator (10) having an interior profile surface and a rotor having an exterior profile surface. The stator tube is formed from the sheet metal spiral round to generate an interior profile, with an adjacent edge of the spiral wound sheet being secured together. Substantially uniform thickness elastomeric layer (20) form down interior surface of the stator tube. A rotor (30) is rotatable within the stator tube and the elastomeric layer of an operation of pump/motor.

Abstract: A pumping system 10 is provided for pumping fluid from a downhole well to the surface through a production tubing string well. A rotatable drive rod 18 extends from the surface to power the downhole pump, and includes a plurality of rod couplings. The downhole pump includes a pump stator 22 and a rotor 24 rotatable within the pump stator. A lifting member 36 provided at the upper end of the stator is engaged by a drive coupling 34 to retrieve the pump from the well. The lifting member has an internal shoulder 44 tapered radially inwardly and upwardly, such that a rod coupling engages the internal shoulder and passes through the lifting member as the rotor is pulled upward.